Fine grading device for rubber tire road grader

ABSTRACT

A grading blade and parallel rotary auger are supported on an auxiliary frame transversely with respect to a grader vehicle from which the frame is supported with the auger being connected to the blade for unitary pivotal movement about a pivot point on the frame between the front of the blade and the rear of the auger in general vertical alignment with the cutting edge of the blade so that the height of the auger can be pivotally adjusted by hydraulic cylinder means with respect to the cutting edge of the blade for differing soil conditions by pivoting the auger and blade with there being a negligible vertical displacement of the cutting edge of the blade; an automatically operable control means actuates hydraulic cylinders supporting the auxiliary frame from the vehicle in response to signals from a guide line extending along the path of movement of the vehicle for maintaining the cutting edge of the blade at a given elevation with respect to the guide line regardless of the height of the auger with respect to the cutting edge of the blade as adjusted by the operator for differing soil conditions.

United States Patent Brown 1 Sept. 26, 1972 [72] Inventor:

Robert Brown, Chesapeake, Va. 731 Assignee: Brohigbu, Ltd., Norfolk, Va.

[22] Filed: Aug. 11, 1970 [21] Appl. No.: 62,917

[52] US. Cl. ..172/4.5, 172/72, 172/785, 37/108 [51 1 Int. Cl. E02f3/76, A0lb 49/02, 1302f 3/12 [58] Field of Search ..'l72/785, 779,-72,71, 4.5, 172/784; 37/108 [56} References Cited UNITED STATES PATENTS3,490,539 1/1970 l-lilmes et a1 ..172/4.5 3,568,778 3/1971 Swisher et a1..172/785 1,883,404 10/1932 Ronning ..172/7l 3,423,859 1/1969 Swisher eta1 ..37/108' Primary Examiner-Robert E. Pulfrey AssistantExaminer-Stephen C. Pellegrino Attorney-Mason, Fenwick & Lawrence 5 7ABSTRACT A grading blade and parallel rotary auger are supported on anauxiliary frame transversely with respect to a grader vehicle from whichthe frame is supported with the auger being connected to the blade forunitary pivotal movement about a pivot point on the frame between thefront of the blade and the rear of the auger in general verticalalignment with the cutting edge of the blade so that the height of theauger can be pivotally adjusted by hydraulic cylinder means with respectto the cutting edge of the blade for differing soil conditions bypivoting the auger and blade with there being a negligible verticaldisplacement of the cutting edge of the blade; an automatically operablecontrol means actuates hydraulic cylinders supporting the auxiliaryframe from the vehicle in response to signals from a guide lineextending along the path of movement of the vehicle -for maintaining thecutting edge of the blade at a given elevation with respect to the guideline regardless of the height of the auger with respect to the cuttingedge of the blade as adjusted by the operator for differing soilconditions.

14 Claims, 7 Drawing Figures PATE'NTEDserzs m2 sum 1 OF 4 INVENTOR1205621 L. BROWN ATTORNEYS PATENTi-jnsrrzs I972 SHEET 2 BF 4 ATTORNEYSwas PATENTEDssrzs m2 sum 3 or 4 INVENTOR 2o BERT L. Bxzowu BY was mg iATTOR I JEYS PATENTEDsms m2 SHEET l 0F 4 INVENTOR Qoeelrr L. BROWN 01asaw a'wwufiJ iiams FINE GRADING DEVICE FOR RUBBER TIRE 7 ROAD GRADERUnfortunately, the prior known systems have frequently'failed to provideadequate accuracy in maintaining a desired grade level notwithstanding.thefact thatsuch machines have been extremely complicatedandconsequently expensive to manufacture and maintain. Moreover, many ofthe prior known systems have been in the form of unitary machinescomprising a driven support vehicle with the grading means fixed to thevehicle and. supported therefrom. Consequently, such devices have beenmuch more expensive than wouldlbe the case if the grading means persecould be connected to a conventional vehicle such as a conventionalgrader.

The obvious desirability of being able to, mount'a grading attachment ona conventional grader is complicated by the large number ofconventionalgraders of different sizes, models and manufacturers whichare presently in use.

Therefore, there has been an unmet need prior to this invention for ahighly accurate fine grading device capable of providing a. fine gradedsurface within minimum tolerancesbut also being capable of use withconventional currently available grading equipment.

lt is the object of thisinvention to provide anew and improved finegrading devicecapable of high grading accuracy and also capable ofbeingmounted on a conventional road grading machine. I I v Obtainment of theobject of'thisinvention has been achieved through the provision of agrading device which can be attached to a conventional road grader andwhich includes a blade extending transversely across the path'ofmovement of the grader with a rotary auger being closely spacedforwardlyof theblade. The

rotary auger is continuously driven by hydraulic motor means forremoving the majorportion of the earth in front of the blade anddepositing it alongside the work path as the grader moves along thesurface being graded. In fact,"optimum grading accuracy is obtained byhaving the blade remove only a small percentage of the total earth beingremoved during the passage of the device along the work path.

The auger and the blade are unitarily connected together on an auxiliarysupport frame for vertical ad justment by automatically controlledhydraulic cylinder means which is controlled by a guide line stretchedalong each or either side of the work path. In practice, the lower orcutting edge of the blade should always be agiven fixed distance belowthe guideline. This fixed distance is maintained by constant monitor-'ing of the guide line by conventional means as the machine moves alongthe work path and consequent control of the cylinders supporting theblade and auger. However, it has been observed that optimum gradingaccuracy can best beobtained in different soil conditions by varying theheight of the auger with respect to 2. V the cutting edge of the blade.This height variation is manually maintained by the operator of thedevice in accordance with the nature of the soil through which the bladeand auger are being moved, However, this adjustment of the height of theauger with respect to the blade should be made witha minimumamount ofvertical displacementof the lower edge .of the blade in order tomaintain a'fixed vertical distance between the lower edge of the bladeand the guide line. In other words,.the vertical distance between thelower edge of the auger and the lower edge of the blade which determinesthe amount of bite that the auger takes of the-earth in the work .pathas it is slowly advanced alongthe work path should be adjustable "with aminimum variation in the height of the blade cutting edge.

achieved by this invention through the use of a unitary connectionbetween the blade and the auger so that they are supported by a unitaryframework with this framework being mounted for pivotal-movementabout anaxis spaced substantially in vertical alignment with the cutting (lower)edge of the'blade forward of the front face of the blade between theblade and the auger. The pivot-axis is also in substantial horizontalalignment with the axis of rotation of the auger. Consequently, thiscritical location .of the :pivot axis provides a substantial verticaldisplacement of the auger with respect to the blade when the blade andauger are unitarily pivoted with practically no vertical displacement ofthe blade occurring.

The entire inventive assembly can be attached to conventionalexisting-control arms of a conventional road grader by' theautomatically controlled doubleacting hydraulic cylinders connected'toball and socket connectors on the grader. The front of the auxiliaryframe is also connected to the grader-by conventional ball and socketarrangement. The ball and socket connectors are those that arecurrently'employed for supporting a conventional blade frame on "roadgraders presently in use. Consequently, the fine grading attheelimination of all slippage of the-rear drive wheels of the grader whicharepassing over the surface being graded. Such slippage or spinning ofthe wheels creates indentations in the finished surface andeausestheentire machine to settle downwardlyso suddenly that it isdifficult .for 'the automatic control device system to .react in time tomaintain a finished surface that is smooth and at the correct elevation.The adjustably mounted rotary auger precedingthecutting edge of theblade is vertically adjustably mounted so :that the cutting edge of theblade removes only a small amount of material from the surface beinggraded and the'forward driving power conveyed through the drive-wheelsis consequently substantially reduced. Moreover, the auger bite can beadjusted to compensate for variations in density or hardness of the soilto prevent spinning of the wheels as the grader moves from one typeofsoil to another. Since the auger removes the major portion of the soilbeing'removed, along the work path and this removal is effected entirelyby virtue of rotation of the auger, the resistance to forward movementof the grader is much less than would be the case if the blade were thesoledev ice for removing the soil above the grade level.

It is essential that the grader be capable of advancing at a very slowrate of speed so that the automatic control device for maintaining theheight of the blade at the desired elevation have sufficient reactiontimejin which to make corrective movements. This slow speed slow drivedevices on the grader and high power requirements of the hydraulic motorfor driving the auger are met by adding an auxiliary high capacityhydraulicpump to the motor grader, power take-off shaft.

Other objects and advantages of the subject invention will be betterunderstood from the following specification and claims when read inlight of the-.accompanying drawings in which:

FIG. 1 is a perspective view of the preferred embodiment-of theinventive concept;

FIG. 2 is a side-elevational view of the preferred embodiment withportions removed for clarity;

FIG. 3 is a plan view of the preferred embodiment; FIG. 4 is a sectionalview taken along lines 44 of FIG. 3; A FIG.-5 is a sectional view takenalong lines 5-5 of FIG. 4; I

FIG. 6 is a sectional view taken along lines 66 of FIG. 3; and t FIG. 7is a sectional view. taken along lines' 7 7 of FIG. 3. 1 t

is accomplished by using a very low travel gear or other Turning firstto FIG. 2, it will be seen thatthe I preferred embodiment of theinvention, which is generally designated 10, is associated with aconventional road grader 11 having drive wheels 12 and steering controlwheels '13 on an elongated main frame member 14 for supporting workattachments depending therefrom. Additionally, the grader is providedwith adrive motor for driving wheels'l2 and the various en gineaccessories. The preferred embodiment of the invention is suspended fromthe main frame 14 of the conventional grader by ball and socketconnections 15 attached to control arms 16 (only one of which is shownin FIG. 2) which extend along each side of frame 14. Arms 16 arenormally employed for supporting a conventional grader blade.

The preferred embodiment includes a main attachment frame generallydesignated F and which includes a horizontal draw bar 20, an endconnector frame member 22 (FIG.6), a semi-circular arcuate frame member24 (FIG. .4) and a transversely extending main cross piece 26 (FIGS. 1and 4) which provides support for the other components of the gradingattachment.

Draw. bar comprises a forward portion consisting of first and secondparallel channel or box frame. members 28 and 30 (FIGfl) which have aconnector plate 32 welded to their forward ends. A second connectorplate 34 is welded to the rearmost end of the end connector frame 22 andthe connector plates 32 and 34 are bolted together to provide a fixedrigid connection cal bearing sleeves 66 (FIGS. 7 and 6) which provide abetweenthe elements 28, 30 and 22. The purpose of providing thedetachable connection between these elements is to reduce the overallsize to enable loading of the attachment, upon a truck fortransportation. Otherwise the length of the components would exceed moststatutory width lengths and could' not be legally transported in manystates. Additionally, a plurality'of connector frame members 22 havingdifferent length and height dimensions can be 'provided for enablingconnection of the device to different road graders in which thepositions of thefemale pivot socket82 will vary. Moreover, the size ofthe male'connector ball 80 can alsobe varied in order to accommodatevarious female pivot sockets of different sizes. Consequently, thedevice will be interchangeably mountable upon a wide variety of roadgraders having different height female pivot sockets and various framelengths.

The rearmost portion of the draw bar 20 is formedof a pair of identicalframe components 36. and 38 connected on their forward ends by a curvedplate 40 (FIG. 6) and which are connected to the upper surface of theframe components 28 and 30 respectively to extend rearwardly for pivotalconnection to the transverse main cross piece 26. This pivotalconnection of components 36 and 38-to cross piece 26 is enabled by meansof a pivot pin 42 mounted in a bracket'44extending from the .rearmostends of members 36 and 38 and a pair of bracket plates '46 and 48 weldedto the front surface of cross piece 26. Pin 42 extends through bracket44 and plates 46, 48 as shown in FIG. 6.

A brace frame 50 is attached to the upper surface frame components 28and 30 and has a top'plate 52 1 connected to the rear of the components36, 38. A curved plate 54 completes a curved opening through the braceframe through which arcuate frame 24 ex- 4 lows frame 24 etc. to pivotabout pin 42 by virtue of the fact that the ends of frame 24 areweldingly connected to each'end of the main transverse frame componentFirst and second curved vertically extending pivot support plates 58 and60 are respectively welded to the extreme ends of the main transverseframe component 26 and respectively have horizontal arms 58 and 60embracingly curving around the rear portion of thearcuate frame member24 as shown in FIG. 1; The horizontal arms 58 and 60" are welded to theexternal surface of the curved frame 24 as shown in FIG. 4.

Plates 58 and 60 extend downwardly to terminate at their lowermost endsin pivot shoe means 62 and 64 (FIG. 3) respectively welded to theirlower ends. The pivot shoe means 62 and 64 respectively supportidentipivotal support for a bladeassembly to be discussed hereinafter.

It should be noted at this point that the main attachment or auxiliaryframe F.c onsists of a unitary structure comprising the arcuate frame24, the main transverse member 26, draw bar elements 36, 38, 28 and 30and thepivot support plates 58 and 60. Additional strength and rigidityis provided the frame F by means of a rearwardly extending brace plateextending rearwardly from the main transverse frame component 26adjacent the entire middle thereof, gusset plates 72 and 74 respectivelywelded adjacent each end of member 26 and to the pivot support plates 58and as best shown in FIG. 3 and a pair of rod brace members 76 welded tothe lower ends of the pivot support plates 58 and 60 and to plate on themiddle portion of member 26 as clearly shown in FIG. 3. Additionally, aforwardly extending linear brace plate 78 extends forwardly from themain transverse frame component 26 along the front face thereof andalong the entire length thereof as best shown in FIG. 1.

Support for the forwardmost end of the frame F is provided by a pivotball type male connector member 80 attached to the forward end of theconnector frame 22 and receivable in a conventional female pivot socket82 on the grader frame as best shown in FIGS. 2 and 6. The rear portionofthe frame F is supported by ball and socket connectors on supportbracket plates 84 and 86 extendingupwardly from the upper surface ofarcuate frame 24 and connected to piston rods.8 8 and 90 of controlcylinders 92 and 94 which have ball socket connectors 15 attached totheir uppermost ends. The ball and socket connectors 15 are connected tothe control arms 16 of the grader as has been noted previously.

Bearing sleeves 66 which are welded to the forward ends of pivot shoes62 and 64 provide support for a scraper blade which extendsperpendicular to the path of travel of the grader 11. Support for blade100 is provided by'a pair of pivot pins 102 which are each mounted onthe forward end of and between a pair of bracketplates 104. Bracketplates 104 are attached to blade I00 and extend forwardly from the frontface 101 of blade 100 as shown in FIG. 7. It shouldfbe noted that thepivot pins 102 are located in substantial vertical alignment with thelower edge of the blade 100. It should also be noted that the pivot shoemembers 62 and 64 each extend forwardly between two of the plates 104through respective openings in blade 100 to terminate in front of theforward, surface 101 of the blade in the manner illustrated by pivotshoe 64 in FIGS. 6 and 7. It is this construction which provides forpivotal movement of the blade 100 about the axes of pins 102.

A rotary auger 106 is supported for rotation in bearings mounted inauger support plates 108 and 110 which are respectively pivotallyconnected to blade 100 by pins 114 and 116 extending from bracketsmounted adjacent the top of the front face 101 at each end of the blade100. The purpose of the pins 114 and 116 is to provide for initialpivotal adjustment of the auger support plates 108 and 110 and auger 106supported thereon with respect to the blade 100. Following suchadjustment, the support plates 108 and 110 and the supported auger 106are locked in fixed relationship with respect to the blade 100.

FIGS. 6 and 7 illustrate the manner in which the auger 106 is initiallyadjustably positioned with respect to the blade 100. Specif cally, therear side of blade 100 is provided with a pair of rearwardly extendingadjustment brackets 118 and 119 (FIG. 3) which are welded to the bladeadjacent each end thereof above a rear brace plate 120 extending alongthe length of blade 100 on the rear face of the blade. Identical rod andsleeve adjustment means are pivotally connected to the brackets 118 and119 by a pivot pin 124 and to the upper or rearmost end of the supportplates 108, 110 by a pivot pin 126.

Adjustment of the two adjustment means 122 connecting each end of blade100 to the auger support plates 108, '1 10 serves to pivot the augersupport plates 110 and 108 about the pins 114 and 116 fixed to the endsof blade 100. Consequently, the position of the auger 106 isadjustedwith request to blade 100 is an obvious manner as shown in FIG.7. Once the desired adjustment has been achieved, no further adjustmentis normally necessary and blade 100, auger support'plates 108, 110 andauger 106 constitute a unitary structure.

'Additional threaded rod members 134 and 136 (FIG.

3) extending betweenthe blade and the auger support plates 108 areprovided for locking the blade and auger in fixed relative positionfollowing the adjustment thereof. v

It is emphasized that the blade 100, auger support plates 108, 110 andauger 106 are consequently fixedly connected to each other to constitutea unitary structure. This unitary structure is pivotally supported bycoaxial pins 102 fixed to blade 100 and pivotally extending throughsleeves 66 on the forward ends of pivot shoes 64 and 62 as waspreviously discussed. Therefore, the auger 106and the blade 100 whichare connected by the elements 108, 110 and 122 pivot about the axis ofpins 102.

Pivotal movement of the unitary blade-auger structure 100, 106 etc. forlifting or lowering the auger is enabled by first and second unitadjusting places 138 and 140 which are welded to the rear side of theblade 100 adjacent back brace plates 141 as best shown in FIG. 3. Theupper ends of plates 138 and 140- are respectively connected to cylinder138' and 140 which are pivotally connected to frame members 141extending from arcuate frame 24 as shown in FIG. 1.

Auger 106 is driven by a hydraulic drive motor 142 (FIGS. 1 and 3)through a step-down transmission 144 connected to the auger supportplate 108. The output of step-down transmission 144 is to a drivesprocket in a chain housing 146 on the right side of support plate 108as viewed in FIG. 4. A chain 148 is driven by the output from thetransmission 144 and extends about a sprocket on an auger drive shaft150 extending through auger support plate 108. Consequently, rotarymovement is imparted to the auger 106 from the motor 142. A separateidentical hydraulic motor could be mounted on the plate 110 if suchshould be desired; however, it

has been found that a single high power motor 142 is adequate fordriving the auger. However, a great deal of power is required fordriving the auger and it is necessary to provide an auxiliary hydraulicpump to be driven by the grader motor. The hose connections etc. foroperating the hydraulic motor 142 are not shown in the drawings sincesuch would merely serve to clutter the drawing and obscure the trueinvention.

Auger 106 comprises a spiral plate extending outwardly'from a heavy bodycylinder 162 along the entire, length of the body cylinder.Additionally, the auger is provided with a plurality of intermediatedigger teeth 164 positioned intermediate the adjacent convolutions ofthe spiral blade 160 which extend outwardly radially approximately oneor two inches (depending upon soil conditions) beyond the outerperiphery of blade 160 for dislodging rocks etc. as the auger is rotatedin the direction of the arrow in FIG. 6. A shield 166 extends forwardlyfrom the upper edge of the blade 100 to prevent such material from beingthrown rearwardly toward the operator by the rotation of the auger 106.

A control means support beam 180 extends outwardly from a hollow boxchannel. 182 connected to the top of the main transverse member 26. Sucha beam 180 extends from each side of the device andis adjustablyretained by clamping means 186 associated with the channel 182 in anobvious manner. Conventional line detecting switch means, sensors ortracers 190 are supported on the'ends of the beam 180 for detecting aconventional wire or line 192 extending along each side of the path ofmovement of the machine. The detecting means 190 etc. is conventionaland forms no part of this invention. However, it should beunderstoodthat the'detecting means 190 etc. provides electric overhydraulic signals to the supporting cylinders 92 and 94 for raising andlowering the blade to maintain the lower or cutting edge of the blade100 a fixed vertical distance below the guide lines 192.

Ithas been found that optimum accuracy in grading can be obtained byadjusting the pivotal position of the auger 106. and the blade 100 byactuating the pivot cylinders 138' and 140' for pivoting the plates 138and 140 along with the blade 100 and auger 106. Such adjustment isnormally made by the operator as the device goes through varying typesof soil. However, while this adjustment causes a substantial variationin the height of auger 106, substantially no vertical variation of thelower or cutting edge of the blade 100 is caused by such pivotaladjustment as is evidenced from inspection of FIG. 7 of the drawingswhich illustrates two different positions of the blade and the auger aswould be caused by actuation of cylinders 138 and 140 to vary the heightof the auger 106. Such adjustment serves to vary the bite taken by theauger as it is moved forwardly through the soil 200 being graded. It hasbeen found that optimum grading accuracy can easily be obtained with theauger 106 removing the majority of the soil and only a small percentageof the soil being removed 'by'blade 100. Normally, the best results areobtained with thelowermost portion of the digger teeth 164 on auger 106being spaced approximately even with or slightly above the lower orcutting head edge of blade 100. Therefore, the subject device serves toprovide an extremely accurate .grade as the grader 11 is moved slowlyforward with the auger 106 rotating in the directionof the arrow in FIG.2. Auger 106 removes the majority of the earth being graded and blade100 provides the finishing accuracy Grader 11 is normally driven at avery slow speed of approximately one mile perhour and auger 106 isrotated at approximately 80 rpm. The necessary slow forward speed ofmovement requires the use of an extra low gear in the grader.

It should be understood that numerous modifications of this inventionwill undoubtedly occur to those skilled in the art; however, theinventionis to be limited solely by the appended claims.

I claim:

1. A highly accurate grading means supported on a main attachment framesupported on a power driven vehicle having a main frame and drive meansfor movement along a path to be graded, said grading means comprisingelongated blade means having a lower cutting edge supported by pivotalsupport means connected to said main attachment frame, said blade meansextending substantially transverse to the path of travel of saidvehicle, linkage connecting means connected to and extending from saidblade means, elongated rotary earth cutting auger means supported by andconnected to said linkage connecting means having an axis of rotationparallel, to said blade means positioned for rotation immediatelyforward of said blade means, control means for moving said auxiliarysupport frame vertically for maintaining the lower edge of the blade ata desired elevation, said pivotal support means supporting said blademeans, said linkage connecting means and said rotary auger means forunitary pivotal movement about a pivot axis positioned forward of thefront surface of said blade means between the front surface of saidblade means and the axis of rotation of saidj rotary auger and insubstantial vertical alignment with the lower cutting edge of saidblade, and actuator means for unitarily pivoting said auger and saidblade about said pivot axis for adjusting the height of said auger withrespect to the surface being graded without any substantial change inthe elevation of the lower cutting edge of said blade with respect tothe surface being graded.

'2. The invention of claim 1 wherein said earthcutting auger includes aplurality of radially extending digger teeth and a spiral blade.

3. Theinvention of claim 2 wherein said pivotal support means supportingsaid blade means and rotary auger for unitary movement includes firstand second vertically extending spaced pivot support plate meansextending downwardly from said attachment frame along the rear side ofsaid blade, pivot shoe means extending forwardly from the lower edge ofeach of said pivot support plate means througha respective aperture insaid blade and terminating forwardly of the forward surface of saidblade, a pivot pin means connecting the forward end of each of saidpivot shoes to bracket plates extending forwardly from said blade sothat said blade and auger are pivotally supportedby said pin for pivotalmovement by said actuator means.

4. The invention of claim 1 wherein said pivotal support meanssupporting said blade means and rotary auger for unitary movementincludes first and second vertically extending spaced pivot supportplate means extending downwardly from said attachment frame along therear side of said blade, pivot shoe means extending forwardly from thelower edge of each of said pivot support plate means through arespective aperture in said blade and terminating forwardly of theforward surface of said blade, a Pivot pin means connecting the forwardend of each of said pivot shoes to bracket plates extending forwardlyfrom said blade so that said blade and auger are pivotally supported bysaid pivot pin for pivotal movement by said actuator means.

5. The invention of claim 2 wherein said control means for moving saidattachment frame comprises first and second hydraulic cylindersconnected between the main frame of the vehicle and said attachmentframe whereby actuation of said cylinders serves to vertically move saidblade and said auger.

6. The'invention of claim wherein said linkage connecting means uponwhich said rotary auger means is mounted for rotation comprises firstand second auger support plates each respectively pivotally connectedintermediate its end to each end of said blade for pivotal movementabout an axis transverse to the path of movement of said vehicle withsaid auger being mounted for rotation on one end of said plates andadjustably extendable and lockable adjustment means connecting saidblade and the other ends of said first and second auger support platesfor fixedly locking the relative position of said auger and said bladein a desired position of adjustment.

7. The invention of claim 6 wherein said attachment frame means includesa transversely extending main cross piece, a semi-circular arcuate framemember connected adjacent each end of said transversely extending maincross piece and having its arcuate portion extending forwardlytherefrom, draw bar means extending forwardly from a pivotal connectionconnecting said draw bar means to the middle of said main cross piece,pivotal connection means connecting the forward end of said draw bar tosaid vehicle, and connecting means connecting said forwardly extendingportion of said arcuate frame to said draw bar means with said first andsecond hydraulic cylinders extending from said vehicle being connectedto said arcuate frame for supporting said arcuate frame.

8. The invention of claim 7 wherein said means connecting said arcuateframe to said draw bar comprises removable pin means which, whenremoved, permits pivotal movement of said draw bar with respect to saidarcuate frame and said transversely extending main cross piece to reducethe overall width of the grading means by permitting movement of theauger and blade to a canted position relative to the axis of thesupporting vehicle for movement to a different location.

9. The invention of claim 8 wherein said draw bar comprises a forwardportion consisting of first and second parallel frame members, aconnector frame removably connected to the forward end of said parallelframe members and a pair of rear frame components extending parallellyfrom the upper surface of said forward parallel frame components forconnection to said transversely extending main cross piece.

10. The invention of claim 1 wherein said actuator means for unitarilypivoting said auger and said blade about said pivot axis includes firstand second hydraulic cylinder means connected between said attachmentframe and said blade so that actuation of said first and second cylindermeans serves to unitarily pivot said blade, said linkage connectingmeans and said rotary auger.

11. The invention of claim 10 wherein said pivotal support meanssupporting said blade means and rotary auger for unitary movementincludesfirst and second vertically extending spaced pivot support platemeans extending downwardly from said attachment frame along the rearside of said blade, pivot shoe means extending forwardly from the loweredge of each of said pivot support plate means through a respectiveaperture in said blade and terminating forwardly of the forward surfaceof said blade, a pivot pin means connecting the forward end of each ofsaid pivot shoes to bracket plates extending forwardly from said bladeso er are pivotally sup orted by al movement by sat that said blade andaug vo actuator said pivot pin for pr means.

12. The invention of claim 11 wherein said control means for moving saidattachment frame comprises first and second hydraulic cylindersconnected between the main frame of the vehicle and said attachmentframe whereby actuation of said cylinders serves to vertically move saidblade and said auger unitarily.

13. The invention of claim 12 wherein said linkage connecting means uponwhich said rotary auger means is mounted for rotation comprises firstand second auger support plates each respectively pivotally connectedintermediate its ends to each end of said blade for pivotal movementabout an axis transverse to the path of movement of said vehicle withsaid auger being mounted for rotation on one end of said plates andadjustably extendable and lockable threaded adjustment means connectingsaid blade and the other ends of said first and second auger supportplates for fixedly locking the relative position of said auger and saidblade in a desired position of adjustment.

14. The invention of claim 13 wherein said frame means includes atransversely extending main cross piece, a semi-circular arcuate framemember connected adjacent each end of said transversely extending maincross piece and having its arcuate portion extending forwardlytherefrom, draw bar means extending forwardly from a pivotal connectionconnecting said draw bar means to the middle of said main cross piece,pivotal connection means connecting the forward end of said draw bar tosaid vehicle, and connecting means connecting forwardly extendingportion of said arcuate frame to said draw bar means with said first andsecond hydraulic cylinders extending from said vehicle being connectedto said arcuate frame for supporting said arcuate frame.

1. A highly accurate grading means supported on a main attachment framesupported on a power driven vehicle having a main frame and drive meansfor movement along a path to be graded, said grading means comprisingelongated blade means having a lower cutting edge supported by pivotalsupport means connected to said main attachment frame, said blade meansextending substantially transverse to the path of travel of saidvehicle, linkage connecting means connected to and extending from saidblade means, elongated rotary earth cutting auger means supported by andconnected to said linkage connecting means having an axis of rotationparallel to said blade means positioned for rotation immediately forwardof said blade means, control means for moving said auxiliary supportframe vertically for maintaining the lower edge of the blade at adesired elevation, said pivotal support means supporting said blademeans, said linkage connecting means and said rotary auger means forunitary pivotal movement about a pivot axis positioned forward of thefront surface of said blade means between the front surface of saidblade means and the axis of rotation of said rotary auger and insubstantial vertical alignment with the lower cutting edge of saidblade, and actuator means for unitarily pivoting said auger and saidblade about said pivot axis for adjusting the height of said auger withrespect to the surface being graded without any substantial change inthe elevation of the lower cutting edge of said blade with respect tothe surface being graded.
 2. The invention of claim 1 wherein saidearth-cutting auger includes a plurality of radially extending diggerteeth and a spiral blade.
 3. The invention of claim 2 wherein saidpivotal support means supporting said blade means and rotary auger forunitary movement includes first and second vertically extending spacedpivot support plate means extending downwardly from said attachmentframe along the rear side of said blade, pivot shoe means extendingforwardly from the lower edge of each of said pivot support plate meansthrough a respective aperture in said blade and terminating forwardly ofthe forward surface of said blade, a pivot pin means connecting theforward end of each of said pivot shoes to bracket plates extendingforwardly from said blade so that said blade and auger are pivotallysupported by said pin for pivotal movement by said actuator means. 4.The invention of claim 1 wherein said pivotal support means supportingsaid blade means and rotary auger for unitary movement includes firstand second vertically extending spaced pivot support plate meansextending downwardly from said attachment frame along the rear side ofsaid blade, pivot shoe means extending forwardly from the lower edge ofeach of said pivot support plate means through a respective aperture insaid blade and terminating forwardly of the forward surface of saidblade, a pivot pin means connecting the forward end of each of saidpivot shoes to bracket plates extending forwardly from said blade sothat said blade and auger are pivotally supported by said pivot pin forpivotal movement by said actuator means.
 5. The invention of claim 2wherein said control means for moving said attachment frame Comprisesfirst and second hydraulic cylinders connected between the main frame ofthe vehicle and said attachment frame whereby actuation of saidcylinders serves to vertically move said blade and said auger.
 6. Theinvention of claim 5 wherein said linkage connecting means upon whichsaid rotary auger means is mounted for rotation comprises first andsecond auger support plates each respectively pivotally connectedintermediate its end to each end of said blade for pivotal movementabout an axis transverse to the path of movement of said vehicle withsaid auger being mounted for rotation on one end of said plates andadjustably extendable and lockable adjustment means connecting saidblade and the other ends of said first and second auger support platesfor fixedly locking the relative position of said auger and said bladein a desired position of adjustment.
 7. The invention of claim 6 whereinsaid attachment frame means includes a transversely extending main crosspiece, a semi-circular arcuate frame member connected adjacent each endof said transversely extending main cross piece and having its arcuateportion extending forwardly therefrom, draw bar means extendingforwardly from a pivotal connection connecting said draw bar means tothe middle of said main cross piece, pivotal connection means connectingthe forward end of said draw bar to said vehicle, and connecting meansconnecting said forwardly extending portion of said arcuate frame tosaid draw bar means with said first and second hydraulic cylindersextending from said vehicle being connected to said arcuate frame forsupporting said arcuate frame.
 8. The invention of claim 7 wherein saidmeans connecting said arcuate frame to said draw bar comprises removablepin means which, when removed, permits pivotal movement of said draw barwith respect to said arcuate frame and said transversely extending maincross piece to reduce the overall width of the grading means bypermitting movement of the auger and blade to a canted position relativeto the axis of the supporting vehicle for movement to a differentlocation.
 9. The invention of claim 8 wherein said draw bar comprises aforward portion consisting of first and second parallel frame members, aconnector frame removably connected to the forward end of said parallelframe members and a pair of rear frame components extending parallellyfrom the upper surface of said forward parallel frame components forconnection to said transversely extending main cross piece.
 10. Theinvention of claim 1 wherein said actuator means for unitarily pivotingsaid auger and said blade about said pivot axis includes first andsecond hydraulic cylinder means connected between said attachment frameand said blade so that actuation of said first and second cylinder meansserves to unitarily pivot said blade, said linkage connecting means andsaid rotary auger.
 11. The invention of claim 10 wherein said pivotalsupport means supporting said blade means and rotary auger for unitarymovement includes first and second vertically extending spaced pivotsupport plate means extending downwardly from said attachment framealong the rear side of said blade, pivot shoe means extending forwardlyfrom the lower edge of each of said pivot support plate means through arespective aperture in said blade and terminating forwardly of theforward surface of said blade, a pivot pin means connecting the forwardend of each of said pivot shoes to bracket plates extending forwardlyfrom said blade so that said blade and auger are pivotally supported bysaid pivot pin for pivotal movement by said actuator means.
 12. Theinvention of claim 11 wherein said control means for moving saidattachment frame comprises first and second hydraulic cylindersconnected between the main frame of the vehicle and said attachmentframe whereby actuation of said cylinders serves to vertically move saidblade and said auger unitarily.
 13. The invention of claim 12 whereinsaid linkage connecting means Upon which said rotary auger means ismounted for rotation comprises first and second auger support plateseach respectively pivotally connected intermediate its ends to each endof said blade for pivotal movement about an axis transverse to the pathof movement of said vehicle with said auger being mounted for rotationon one end of said plates and adjustably extendable and lockablethreaded adjustment means connecting said blade and the other ends ofsaid first and second auger support plates for fixedly locking therelative position of said auger and said blade in a desired position ofadjustment.
 14. The invention of claim 13 wherein said frame meansincludes a transversely extending main cross piece, a semi-circulararcuate frame member connected adjacent each end of said transverselyextending main cross piece and having its arcuate portion extendingforwardly therefrom, draw bar means extending forwardly from a pivotalconnection connecting said draw bar means to the middle of said maincross piece, pivotal connection means connecting the forward end of saiddraw bar to said vehicle, and connecting means connecting forwardlyextending portion of said arcuate frame to said draw bar means with saidfirst and second hydraulic cylinders extending from said vehicle beingconnected to said arcuate frame for supporting said arcuate frame.